Lock washer



Sept- 3, 1929. w. E. ZINNBAUER 1,726,972

LOCK WASHER Filed July 15, v1927 l E gum/nto@ l' s@ M atten "Ng-13 Patented Sept. 3,

PATENT OFFICE.

WILLIAM ZINNBAUER, F DETROIT! MICHIGAN.

I Locri WAsHEn.

Application led July 15,v

This invention relates to lock washers and the object -of the invention is to provide a lock washer having spring lugs which cannot be completely flattened by tightening of the.

V nut with which the lock washer is utilized.

Another objectof the invention is to pro?` l vide a lock washerprovided with spring lugs adapted'y to bite Ainto the surface-on whic it is positioned and into the nut when the nut 1o is tightened down thereon to prevent removal ofthe nut. l f

Another object of the invention is to provide a lock washer which limits the movement of the'nut toward the washer support and in which the spring lugs maintain their'resiliency at all times. I

These objects and the Aseveral novel featuresof the invention are hereinafter more fully described and claimed and the preferred form of construction by which these objects are attained is lshown inthe accompanyingdrawings in 'which- Fig. l'is a plan view of alock washer embodyingmy'invention. 1

Fig. -2 is a lsectionthrough the lock washer as mounted on a bolt or stud taken on line 2 2 of Fig. 1. l...

Fig. 3 is an enlarged section taken on line 3 3 of Fig. 1.v p Fig. 4 is a perspective detail showing one of the spring 1u s of the lock washer.

The lock was er comprises a metal disc having a central aperture 1 and an annular bead 2 formed in the metal near .the outer edge. When the annular bead 2 is formed,the

outer edge 3 is depressed below the portion of the washer within the bead 2, as shown in -F ig. 2. In this manner a space 4 is provided between the central portion 5 of the 40 washer and the nut 6 and a space 7 is provided Vbetween the `central portion of the Washer and the member on which the flange 3 of the washer rests. The inner edge of the washer about the aperture 1 is provided with five notches 8 and the washer is sheared or slitted at 9 on opposite sides of each notch 8 in the form of an arc. This provides five separate.

1927. serial No. 205,867.

12 extend below the ange 3. The washer is tempered so that the lugs will maintain theirresiliency and the lugs 10 are arcuate in form andextend about the circumference of the bolt or stud 13.

In operation the lock washer is positioned over a bolt or stud with the spring lugs in the position shown in Figs. 1 and 2. As the nut 6 is threaded down onto the bolt or stud 13'it passes over the spring ends 11 of the lugs 10 in a clockwise'directionthus compressing the ylugs' between the nut 6 and the member'l4 on which the washer is positioned. The compression of the springlugs is limited however by the flange 3 engaging the member on which it rests and by the nut 6 engaging the bead 2 on. t-he washer. This prevents the nut from being turned down until the lugs 10 are iattened out. In the ordinary lock washer having spring lugs of any common form and not provided with the bead 2 the tightening of the nut actually lattens the spring lugs and breaks down or crushes the lines of stress in-the lugs to such an extent that when the nut is removed the lugs will not spring back to their former'- position. With this type Vof washer after the nut has been turned down tightly the washer has no more locking action than a common washer and as soonl as the -nut begins to loosen the spring lugs will not spring out to maintain a tension on the nut. The particular object of my invention is to prevent the crushin of the lines of stress in the spring lugs so t at the spring lugs always maintain a tension on the nut to prevent its loosenin This is accomplished by means ofthe bea 2 and depressedange 3 which prevents the possibility of attening of the spring lugs when tightening up the nut. While the nut is threaded on in av clockwise direction quite readily, the upturned ends 11 of the lugs bite into the nut and the downturnedends 12 bite into the washer supportv so that counter clockwise rotation to remove the nut is -almost impossible except when tremendous -(pressure is applied to the nut. Due to the fact that the spring lugs are not crushed or y ing down of the spring lugs by pressure ap` member having an annular raised bead adjacent to and in spaced relation with its outer edge, the said outer edge about the bead be- `ing depressed below the remainder of the washer, a series of spring lugs formed in the Washer within the saidbead, the said spring lugs extending above the bead on one side of the washer and below the outer edge on the other side of the washer. '4

2. A lockwasher comprising a sheet metal disk having a central aperture, the disk being provided with a raised bead on one side and a depressed iangeon the opposite side, and a series of spring lugs extending from opposite sides of the washer adapted to allow turning of a nut `in one direction thereover and to prevent rotation of the nut in the opposite direction.

3. A lock Washer comprising a sheet metal disk having a central aperture, the disk being provided with a raised bead on one side and a depressed flange on the opposite side` a series of arcuate spring lugs formedl from the metalA disk about the central aperture, one p L'aaera end of each sprin lug being turned upwardly and the opposite end being turned downwardly.

4. A lock washer comprising an annular metal member having an annular raised bead adjacent its outer periphery, the metal on the exterior of the bead being depressed below the remainder of the washer, and a series of spring lugs extending on opposite sides of the washer.

5. A lock washer comprising an annular sheet metal member having an annular raised bead adjacent to and in spaced relation with its outer edge, the said outer edge being depressed below the remainder of the washer, and a series of spring lugs formed from the metal of the washer within the said bead.

6. A lock washer comprising an annular metal member having an annular bead formed therein adjacent the periphery, a series of spring lu s formed in the annular member Within said bead, the bead bein arranged to prevent complete attening o the spring lugs in use. i

7. A lock washer comprising an annular member having an annular bead formed therein and a series of spring lugs extending from opposite sides of said member above and below said bead.

ln testimony whereof l sign this specilication.

LLI lE. ZI AUER, 

